Patent GB-1410584-A (GB)
Title: Apparatus for the external testing of a pipe joint
IPC: G01M3/28
Filed: 1974-06-06
Abstract: 1410584 Testing pipe joints SEAGULL Mfg CO Ltd 6 June 1974 25250/74 Heading G1S A pipe joint testing apparatus comprises a deformable sleeve 46 formed of two semicylindrical parts, the inner periphery of the sleeve having an annular central portion 52 to engage the pipe joint 51 and end seals 53 to engage the pipes 50, a casing formed in two parts in each of which a respective one of the sleeve parts is mounted, the two parts of the casing having joints lying in a plane containing the axis of the sleeve and at an angle to the plane containing the joints between the sleeve parts, means to secure the parts of the casing together, means to supply fluid under pressure to the sleeve and means for monitoring the pressure in the sleeve. The angle between the planes is 5 to 15 degrees, preferably 10 degrees. The sleeve may be of rubber or polyurethane and the centre of curvature of the inner surface of a sleeve part may be displaced away from the sleeve from that of the outer surface. Each casing part includes an outer member 41, an inner member 43 and a metal lining plate 47. The central portion 52 of each sleeve part has an axial groove 55  housing a conduit 56 open at its ends and connecting the grooves 54 formed in the sleeve part with a conduit 57. Conduit 57 is secured to the casing part by nuts 64, 65, and sealed to the sleeve part by a seal 62. In a pressure test, water under  pressure is introduced into one of the conduits 57, and the other one may be used to bleed air from the sleeve, to monitor the pressure in the sleeve, or may be sealed. To prevent the sleeve expanding axially when the pressure fluid is applied, there is provided at each end of the sleeve a collet ring made up of four collet segments 66. Each segment has a sloping face 67 co-operating with a ring 69 having a camming surface 68 whereby axial movement of the segment caused by axial expansion of the sleeve causes the segment to grip the pipe. At the surface of the segments facing the sleeve is provided a facing ring 71 formed of four segments, the joints between which do not coincide with the joints between the collet segments. The two casing parts are provided with yoke elements 15 pivotally supported on a pin 16. One of the casing parts is fixed to the frame 11 by means of a pin 17, and the other is pivoted between open and closed positions by means of two pneumatic rams 24 each connected to the casing part by a toggle linkage 19, 22. To lock the casing parts together, a series of latch members 32 are movable by pneumatic rams 35 into a position in which they engage pins 27, 28 mounted on the casing parts. Pneumatic rams 38 operate via toggle linkages 29, 30 to lock the latching members 32 in the latching position. A fluid supply circuit Fig. 8 (not shown), includes a two stage water pressurization system employing air driven pumps, and an air supply system for operating the pumps and the pneumatic rams. After high-pressure water has been supplied to the sleeve, the supply is cut off and the pressure is monitored on a pressure gauge to determine if a leak is present. As shown in the Figs., the apparatus is applied to a vertical pipe string, and may be mounted from a tripod assembly Fig. 9 (not shown), by means of a pneumatic ram. The two casing parts may be joined by a chain arranged to become taut and thus eject the pipe from the apparatus when the casing is opened Figs. 10, 11 (not shown).